"Relics" are sanctified by definition whereas "corpses" and "remains" (which terms were commonly utilized on this blog) are not. It is interesting that the Bolsheviks immediately started to refer to the "corpses" and "remains" of saints, so as to make them merely historical figures without any connotation of sanctity, as they took them from the churches to be put up as exhibits in museums like Egyptian mummies. Assuming one is addressing even those who are uneducated in "classes" of relics it's best to cut to the chase. Reverence costs nothing. There is quite enough secularization going on as it is.